My Brother HL-2170W printer makes a squeaking noise when it is printing or when the print engine is starting up, such as when waking up from sleep or after closing the front cover. As far as I can tell, the squeaking noise has nothing to do with the toner or drum, but appears to be in the paper feed rollers, as the noise isn't made when the print engine starts up without the paper cassette inserted. There are no print-quality problems, so the only problem is the squeaking noise.
The printer is well out of warranty, and I'm willing to perform simple disassembly, but only as long as the risk of damage is minimal—I do not want to buy another printer. What should I do?